Table Definition and 927 Threads

I came across this problem while studying for my PE exam: I'm not sure what "P_r2" is supposed to represent. Obviously 480 psia is not 697.5 times atmospheric pressure. This is what the table looks like with the "relative pressure" column: How does "relative pressure" relate to the...

I tried to solve the problem like this. 4-1. m d/dt (v_1) = mg sin(theta) - F 4-2. m d/dt (v_2) = R - mg cos(theta) If there is no slip, v_1 = v_2 = 0, so F= mg sin(theta), R= mg cos(theta). In the rotational motion equation, we intergrate 5-1. I omega^2 = 2dmg ( sin theta_f -...

I am calculating the temperature distribution and utilizing the obtained results to calculate the current distribution. In order to do this , I employ a table in which I stock all the current distribution for each value of radius . Subsequently, I aim to identify the radius corresponding to a...

I would like to understand the topic discussed in this thread more. https://www.physicsforums.com/threads/tipping-over-a-table-how-much-overhang.1012197/post-6598527 As I understand it, I can find the load required to tip the table can be calculated by this formula. L<W a/x This is illustrated...

I would like to print a nice PTOTE, written in Latex. So that I could make small modifications before printing it. I have checked on the Internet, but surprisingly couldn't find any really nice one. Ideally, it should contain information like the fusion point, possibly crystallographic...

Question: Answer:

[Mentor Note -- This thread start is outside of the normal scope of PF, but we are allowing it because it's a pretty well-done project for the level of the student] :smile: Hi all, I would like to share my high school engineering project - A Mini Airhockey table with Robotic Defender...

Hello everyone. First post! I am struggling to understand an issue in our (histology) lab. We use large downdraft tables which extract the noxious substances we use, mainly formaldehyde, while we process surgical samples. These tables have a steel cover with lots of holes about 5mm diameter...

I haven't used a log table in a long time and the one I used in High School went from 10 to 99 with four significant figures for the logarithms. I wondered how did Briggs create a log table 400 years ago? How did he find the logarithm of 7(base 10)? I looked around the internet and You Tube and...

I would like a table of Earth mean temperatures going back as far as available. Where can I find that?

\begin{array}{|c|c|c|c|c|c|c|c|c|c|c|c|c|} \hline n & 1 & 2 & 4 & 5 & 8 & 10 & 11 & 13 & 16 & 17 & 19 & 20 \\ \hline \chi_{1}(n) & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 \\ \hline \chi_{2}(n) & 1 & -1 & 1 & 1 & -1 & -1 & -1 & -1 & 1 & 1 & -1 & 1 \\ \hline \chi_{3}(n) & 1 & 1 & 1 & -1 & 1...

I need help. When I press show button it does not show any table and error. Here is the code: package Demo; import java.awt.EventQueue; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.border.EmptyBorder; import javax.swing.table.DefaultTableModel; import...

For part(a), The solution is, However, I made a mistake somewhere in my working below and I'm not sure what it is. Does anybody please know? Thank you! Here is a not too scale diagram at the moment of the collision, ## \vec L = \vec r \times \vec p ## ## \vec L = -y_{com}\hat j \times...

I did this for some work I'm doing and I thought I'd offer the program in case anyone might want it. (And one little question.) It's a Clebsch-Gordon table generator for addition of quantum angular momentums. The TikZ coding is fairly basic, but it's probably my best TikZ work so far, not...

hey, I was searching for a steam table for a long time but I wasn't lucky, I don't know why an n-pentane, iso-pentane or even pentane table is hard to find , so I am here today asking for a steam table for n-pentane or pentane table, forgive me if I was asking too much, Thank you very much you all.

This problem is from MIT's module again. I have a doubt about Newton's Third Law. How is the normal and weight of the book not Newton's 3rd Law pairs? When the book is placed on the table, I imagine that the book's weight exerts a force on the table and the table exerts and equal and...

In both the cases 7 kg mass accelerates towards the right because of the 50N force. The unbalanced forces in both the cases are the force of gravity due to 5kg block and force of friction. Applying Newton's second law of motion to cases 1 and 2 yields the following results for acceleration...

(picture of diagram below)So the task goes like this: gas is ideal. Process 3->1 s adiabatic and in process 1->2 work done is 1200J. Fill the table. I don't know how to calculate work done in an adiabatic process because p2 and V2 are not given and I don't know gama(Cp/Cv). I know that deltaU...

Since ## \varphi(16)=8 ##, it follows that there are ## 8 ## Dirichlet characters modulo ## 16 ##.

I got 13N but is that right because apparently, it's wrong Here's my work: F = mg = 2(10) = 20N F = ma a = F/m = 20/4+2 = 20/6 = 10/3 = 3.3m/s^2 T = mg - ma T = (2kg)(10m/s^2) - (2kg)(3.3m/s^2) = 13.4 N I appreciate it! And if I'm wrong could you show how you got your answer? Thanks

Hi guys, I am not doing homework, it is just suddenly brainstormed this question. What if I place a very small mass like 10kg on the center of a concrete 10m*10m flat table supported by the ground, then how to measure the surface pressure acting on the center and right on the edge? Or the...

Hi PF! Given a .csv file with the first row a name (string) and successive rows doubles, how can I read and manipulate this data in C++? Typically I just google these sorts of questions, but I'm seeing so many links. Do you have one that you recommend, or do you have a function you've written...

What are these sheets with grids and angle references called, that people use on their work tables?

I have a table of values (from my own analysis, not from a textbook) that represents a portion of a periodic function: x y 0 30 1 20 2 10 3 10 4 20 5 30 What function satisfies the table? What I know is that the function is periodic. I was thinking I could use cosine because its...

I have tried solving this by splitting the load into two parallel coplaner loads as the Hint below the question suggests but while i was computing the values i realized that, i'll have 4 variables with only 3 equations. two forces and the two distances to forces from their respective axes. i've...

I have 4 tiny ~7in wooden posts that have cross bracing (let me know if I need to describe the bracing), and I place a solid wooden board on top of the posts then as much weight as possible on the board until the posts break. The posts are equidistant from the center of where the boards and...

It seems the practice is to enter the table with evaporator air intake wetbulb temp and condenser ambient temp. I'm trying to understand the theory that translates these readings into the proper target superheat. Thanks

At the time of release, the equation of motion of blocks A and B T-m_ag = m_aa and T=m_b\omega^2R respectively, where T is the tension in the string. Solving for the acceleration a then gives a=\frac{m_b\omega^2R - m_ag}{m_a}. Not sure what I did wrong or what incorrect assumptions I made...

Hello all, I am looking to get an electronic copy of the Table of Radioactive Isotopes by Edgardo Browne and Richard B. Firestone. I know that we can run software that incorporates this database here: https://www2.lbl.gov/LBL-Programs/Gamquest.html , but I am looking for an electronic copy to...

I'm currently confused in determining whether an image formed by the 1st mirror (the left one) is a real or virtual object for the 2nd mirror. Here is the solution manual: This is what I have in my mind: Since the object is located between the focus and radius point of the first mirror, the...

My take; Let the cat's height = ##c## and the tortoise's height =##t## and the table's height= ##h##, therefore, ##t+ (170-c)=h## ##c+(130-t)=h##. It then follows that, ##t+ (170-c)=c+(130-t)## ##2t+40=2c## ##c=20+t##, therefore, on substituting into ##t+ (170-c)=h##...

I'm designing a table and need to know how much overhang I can have. Assuming the table is completely rigid, is symmetric, and has weight W acting on the CG, how much overhang x can I have? For instance, I know that zero overhang could have L = ∞ (if completely rigid) as the load wouldn't be...

My high school physics days are long ago ;) This is not homework, well, other than it is work, at home. For a real application: Very space constrained "workshop", got a bench drill press, and want to build a table on wheels for it, to be able to move it into a corner when not needed. Those...

Because we use updated bias and not the original bias? Please clear my confusion

How did you find PF?: Google l was asked how hot would our IT space get if we lost all air conditioning. The space is 20' x 15' x 10', We keep set point at 70 F and have 80 kW of load. Assuming this exists in a well insulate container with 20 racks of equipment. Doesn't have to be perfect but...

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In the book, it is stated that if your hand move a distance x, then x/2 is the length of the moving part of the chain because the chain gets “doubled up.” as in the image below. I don't get the meaning of this. For example, if our hand move L metres from initial position, shouldn't the moving...

I started out by drawing a diagram: So I thought I would try torque with the axis of rotation in the center: ##T_1R = \frac{Mr^2}{2}\alpha## and given that ##T_1## is equal to ##F## in the positive direction. ##\alpha = 266.6 \frac{rad}{s^2}## Then knowing the relationship between angular...

Hey! 😊 I want to write a function in Python that returns the multiplication table $20\times 20$. We do that using lists in lists, right? I have written the following : def mul_table() : Prod = [] Table = [] for i in range(21) : for j in range(21) ...

I've just started to learn about Quantum Tunneling and heard that if I were to slap my hand on a table it's theoretically possible for my hand to go through the table. Is this really possible and if so, does the fact that this is even possible provide evidence that we could be living in a...

Hello! I've recently encountered this problem https://www.physicsforums.com/threads/need-major-help.117630/ and solved it and I'm stuck at choosing between 2 solutions. I don't understand why do we need to plug in 0.39 and 0.65 to (1-2x) and NOT to (1-2x)^2. I mean, we were given 2NO2, not just...

Hello everyone, I have to find the average acceleration in the intervals 0m - 30m, 30m - 60m, and 60m - 90m. Here is the table: Position (m) 0 10 20 30 40 50 60 70 80 90 100 Time (s) 0 1,89 2,88 3,78 4,64 5,47 6,29 7,10 7,92 8,75 9,58 My teacher has given us the answers, but we have to...

The resistance y (in ohms) of 1000 feet of solid copper wire at 68 degrees Fahrenheit is y = 10,370/(x^2) where x is the diameter of the wire in mils (0.001 inch). Complete the table. x...60 70 80 90 100 y... Solution: Let x = 60 y = 10,370/(60)^2 y = 10,370/3600 y = 2.8805555556 This...

Hello. How do I add 'x' to 'xy', and the resultant should be <= 1? x + xy = 1 PEMDAS: Step 1: Multiply 'x' and 'y' (2nd term in the equation) Step 2: Add 1st term to 2nd term of the equation Step 1 plus Step 2 should yield value <=1. I know that the curve look like this: 'xy' will give me...

I understand hashing (at least in theory), but I am struggling with actual implementation. I was wondering what the best way to go about this problem was, and this just led to more questions. Now I am confused. 1) The database has to be stored on disk. Let's say it's stored as a folder of...

We know that impulse is $$\vec J = \vec F \Delta t = \Delta \vec p$$ Let ##l, m## be the length of single rod and its mass respectively. Analyzing torques and forces on each rod separately we have: Rod ##AC##: $$F\Delta t +N_x\Delta t = mV_{ac,x} \space\space\text{ eq. }(1)$$ $$F\Delta t\cdot...

Let me imagine a box placed on a table. It has got no acceleration. If I were a person who trusted Newton's laws then I would argue that the net force on the box should be zero. Now in another situation I am an observer outside the Earth and I see that the box is rotating along with the earth...